Zebrafish Core C3.1 Rationale. Core C maintains wild type, transgenic and mutant zebrafish strains for RMNDC investigators. The unique developmental and optical imaging properties of the zebrafish embryo makes it an ideal model to address questions at the heart of the research programs RMNDC investigators. UCD NINDS researchers are internationally recognized and expert in the fields of neurophysiology, neurodevelopment and optical imaging. During the previous award period. Core C removed technical barriers for RMNDC investigators who were interested in using the model system (e.g., Betz, Caldwell, Clouthier, Niswander, Restrepo, Taylor, Williams) but did not have experience or means for maintaining lines. We propose three Specific Aims for Core C that will allow RMNDC members to take advantage of the zebrafish system for neurodevelopmental and behavioral studies. In addition to the 13 current Core C users, the facility will allow access to the zebrafish model to investigators who have not considered its use because of the pragmatic limitations associated with maintaining and breeding zebrafish. In particular, there has been growing interest in complementing rodent studies (e.g.. Core B) with ones done in zebrafish (e.g., Appel, Artinger, Barlow, Clouthier, Macklin, Niswander, Restrepo, Williams), and vice versa. The core will also be a resource for the larger scientific community because transgenic lines will be described on the RMNDC website and made available to the Zebrafish International Resource Center (ZIRC) by the time of the first publication.